JP2015060692A - Fuel cell stack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify handling of components and improve the assembly workability.SOLUTION: In a fuel cell stack 10, multiple power generation cells 12 are laminated. Resin fastening parts 60a to 60c are provided at a first metal separator 22 to a third metal separator 28 which form the power generation cell 12. A connection pin part 62, a second hole part 66a and a third hole part 66b, in which a rebuilt pin 70 is selectively disposed, and a fourth hole part 68 serving as an end part assembly hole part are formed in the resin fastening part 60a. The second hole part 66a, the third hole part 66b, and the fourth hole part 68 are formed in the resin fastening parts 60b, 60c in addition to a first hole part 64 into which the connection pin part 62 is inserted.

Description

  The present invention includes a power generation cell having an electrolyte / electrode structure in which electrodes are arranged on both sides of an electrolyte and a separator, and a terminal plate on both sides in a stacking direction of the stacked body in which a plurality of the power generation cells are stacked. The present invention relates to a fuel cell stack in which an insulating member and an end plate are disposed outward.

  For example, a solid polymer fuel cell employs a solid polymer electrolyte membrane made of a polymer ion exchange membrane. This fuel cell comprises an electrolyte membrane / electrode structure in which an anode electrode and a cathode electrode each having an electrode catalyst (electrode catalyst layer) and porous carbon (gas diffusion layer) are disposed on both sides of a solid polymer electrolyte membrane ( MEA). The electrolyte membrane / electrode structure constitutes a power generation cell by being sandwiched between separators (bipolar plates).

  In general, a fuel cell stack is configured by including a stack in which a predetermined number of power generation cells are stacked, and terminal plates, insulating plates, and end plates are disposed outward on both sides of the stack in the stacking direction. doing. This fuel cell stack is used as, for example, an in-vehicle fuel cell stack mounted on a fuel cell electric vehicle.

  As described above, when stacking a plurality of power generation cells, it is desired to assemble the power generation cells easily and quickly and to efficiently disassemble and assemble the power generation cells. For this reason, for example, a fuel cell disclosed in Patent Document 1 is known.

  In this fuel cell, the separators constituting the fuel cell are fastened by a first resin connector. Therefore, the fuel cell can be efficiently assembled by a simple operation. Furthermore, when disassembling the assembled fuel cell, the first resin coupling body is removed, while the second resin coupling body is disposed in either the first fastening portion or the second fastening portion. Has been. As a result, the fuel cell can be easily and quickly reassembled.

Japanese Patent No. 5043064

  By the way, in the fuel cell stack, for example, a technique of interposing a dummy cell (non-power generation cell) or a heat insulating member configured similarly to the power generation cell as a heat insulating structure between the end of the laminate and the terminal plate is adopted. Has been. For this reason, there are problems that the number of parts is considerably increased and handling becomes complicated, and the assembly workability of the fuel cell stack is lowered.

  The present invention solves this type of problem, and an object thereof is to provide a fuel cell stack capable of simplifying the handling of components and improving the assembly workability satisfactorily.

  The fuel cell stack according to the present invention includes a power generation cell that sandwiches an electrolyte / electrode structure in which electrodes are disposed on both sides of an electrolyte, between separators. A terminal plate, an insulating member, and an end plate are disposed outward on both sides in the stacking direction of the stacked body in which a plurality of power generation cells are stacked.

  In the fuel cell stack, a resin fastening portion and a resin holding portion are formed on the outer peripheral edge of the separator. The resin fastening portion fastens between a plurality of separators arranged in the stacking direction in the power generation cell. The resin holding part hold | maintains the separator which comprises the edge part electric power generation cell arrange | positioned at least in the lamination direction one end to one insulating member.

  The resin fastening portion has a resin protrusion provided integrally with a separator disposed at one end of the power generation cell. The resin fastening portion is formed on a separator other than the separator provided with the resin protrusion, and has a first assembly hole into which the resin protrusion is inserted integrally. The resin fastening portion further includes a second assembly hole portion and a third assembly hole portion that are formed in all the separators and into which a resin connecting member that is a separate member is selectively inserted instead of the resin projection portion. Yes.

  The resin holding portion is formed in all the separators, and has an end assembly hole portion in which an end resin connecting member, which is a separate member, is integrally inserted from the insulating member into the separator of the end power generation cell. .

  According to the present invention, the power generation cell is integrated through the resin fastening portion, and the reassembly operation of the power generation cell can be quickly performed. Moreover, the end power generation cell is integrally held by the insulating member via the resin holding portion. For this reason, it becomes possible to simplify the handling of parts and to improve the assembly workability satisfactorily. Furthermore, since the resin holding part is provided in all the separators, the separator structure can be shared, and the cost can be favorably suppressed.

1 is a partially exploded schematic perspective view of a fuel cell stack according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view of the fuel cell stack taken along line II-II in FIG. 1. It is a disassembled perspective explanatory drawing of the electric power generation cell which comprises the said fuel cell stack. It is front explanatory drawing of the 1st metal separator which comprises the said electric power generation cell. FIG. 5 is a cross-sectional view of the fuel cell stack taken along line VV in FIG. 3. FIG. 4 is a partially exploded schematic perspective view of a fuel cell stack according to a second embodiment of the present invention. FIG. 7 is a cross-sectional view of the fuel cell stack taken along line VII-VII in FIG. 6. It is a disassembled perspective explanatory drawing of the electric power generation cell which comprises the said fuel cell stack.

  As shown in FIG. 1, the fuel cell stack 10 according to the first embodiment of the present invention includes a stacked body 14 in which a plurality of power generation cells 12 are stacked in the horizontal direction (arrow A direction).

  A terminal plate 16a, an insulating plate (insulating member) 18a, and an end plate 20a are sequentially disposed at one end in the stacking direction (arrow A direction) of the stacked body 14 toward the outside. At the other end in the stacking direction of the stacked body 14, a terminal plate 16b, an insulating member 18b, and an end plate 20b are sequentially disposed outward. Second metal separators 26, which will be described later, are disposed at both ends in the stacking direction of the stacked body 14, and the second metal separators 26 are in contact with the insulating members 18a and 18b (see FIGS. 1 and 2).

  The fuel cell stack 10 is integrally held by, for example, a box-like casing (not shown) including end plates 20a and 20b configured in a rectangular shape as end plates. The fuel cell stack 10 may be integrally clamped and held by a plurality of tie rods (not shown) extending in the direction of arrow A, for example. The end plate 20a is provided with fuel gas, oxidant gas and cooling medium supply / discharge ports, but the end plate 20b may be provided with some supply / discharge ports.

  As shown in FIG. 3, the power generation cell 12 includes a first metal separator 22, a first electrolyte membrane / electrode structure (electrolyte / electrode structure) 24a, a second metal separator 26, and a second electrolyte membrane / electrode structure 24b. And a third metal separator 28 is provided. The first metal separator 22, the second metal separator 26, and the third metal separator 28 are configured by a vertically long metal plate such as a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, for example, but using a carbon separator. Also good.

  As shown in FIGS. 2 and 3, the first electrolyte membrane / electrode structure 24a and the second electrolyte membrane / electrode structure 24b are, for example, solid polymer electrolyte membranes in which a perfluorosulfonic acid thin film is impregnated with water. 30. The solid polymer electrolyte membrane 30 is sandwiched between an anode electrode 32 and a cathode electrode 34. The anode electrode 32 constitutes a step MEA having a smaller planar dimension than the cathode electrode 34, but on the contrary, it can have a larger planar dimension than the cathode electrode 34.

  The anode electrode 32 and the cathode electrode 34 are obtained by uniformly applying a gas diffusion layer (not shown) made of carbon paper or the like and porous carbon particles carrying a platinum alloy on the surface thereof to the surface of the gas diffusion layer. And an electrode catalyst layer (not shown) to be formed. The electrode catalyst layers are formed on both surfaces of the solid polymer electrolyte membrane 30.

  As shown in FIG. 3, an oxidant gas inlet communication hole 36a and a fuel gas inlet communication hole 38a are provided at the upper edge of the power generation cell 12 in the long side direction (arrow C direction). The oxidant gas inlet communication hole 36a supplies an oxidant gas, for example, an oxygen-containing gas. The fuel gas inlet communication hole 38a supplies a fuel gas, for example, a hydrogen-containing gas.

  A fuel gas outlet communication hole 38b that discharges fuel gas and an oxidant gas outlet communication hole 36b that discharges oxidant gas are provided at the lower edge of the long side direction (arrow C direction) of the power generation cell 12. A pair of cooling medium inlet communication holes 40a for supplying a cooling medium is provided above both edge portions in the short side direction (arrow B direction) of the power generation cell 12. A pair of cooling medium outlet communication holes 40b for discharging the cooling medium are provided below both edge portions in the short side direction of the power generation cell 12.

  As shown in FIGS. 3 and 4, the surface 22a of the first metal separator 22 facing the first electrolyte membrane / electrode structure 24a is connected to the fuel gas inlet communication hole 38a and the fuel gas outlet communication hole 38b. One fuel gas passage 42 is formed. The fuel gas inlet communication hole 38a and the first fuel gas flow path 42 communicate with each other via a plurality of inlet connection flow paths 43a, while the fuel gas outlet communication hole 38b and the first fuel gas flow path 42 have a plurality of numbers. Communicated via the outlet connection flow path 43b. A part of the cooling medium flow path 44 that connects the cooling medium inlet communication hole 40 a and the cooling medium outlet communication hole 40 b is formed on the surface 22 b of the first metal separator 22.

  As shown in FIG. 3, the surface 26a of the second metal separator 26 facing the first electrolyte membrane / electrode structure 24a is connected to the oxidant gas inlet communication hole 36a and the oxidant gas outlet communication hole 36b. An oxidant gas flow path 46 is formed.

  A second fuel gas channel 48 that connects the fuel gas inlet communication hole 38a and the fuel gas outlet communication hole 38b is formed on the surface 26b of the second metal separator 26 facing the second electrolyte membrane / electrode structure 24b. . The fuel gas inlet communication hole 38a and the second fuel gas flow path 48 communicate with each other via a plurality of inlet connection flow paths 49a, while the fuel gas outlet communication hole 38b and the second fuel gas flow path 48 include a plurality of Through the outlet connection channel 49b.

  A second oxidant gas flow path 50 communicating the oxidant gas inlet communication hole 36a and the oxidant gas outlet communication hole 36b is formed on the surface 28a of the third metal separator 28 facing the second electrolyte membrane / electrode structure 24b. It is formed. A part of the cooling medium flow path 44 is formed on the surface 28 b of the third metal separator 28.

  A first seal member 52 is integrally formed on the surfaces 22 a and 22 b of the first metal separator 22 around the outer peripheral edge of the first metal separator 22. A second seal member 54 is integrally formed on the surfaces 26 a and 26 b of the second metal separator 26 around the outer peripheral edge of the second metal separator 26. A third seal member 56 is integrally formed on the surfaces 28 a and 28 of the third metal separator 28 around the outer peripheral edge of the third metal separator 28.

  Examples of the first seal member 52, the second seal member 54, and the third seal member 56 include EPDM, NBR, fluorine rubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroprene, or acrylic rubber. A sealing member having elasticity such as a sealing material, a cushioning material, or a packing material is used.

  A plurality of resin fastening portions 60a, 60b, and 60c are integrally provided on the outer peripheral edge portions of the first metal separator 22, the second metal separator 26, and the third metal separator 28, respectively. The resin fastening portions 60a, 60b and 60c are made of, for example, PPS (polyphenylene sulfide), POM (polyacetal), PBT (polybutylene terephthalate), PEEK (polyetheretherketone), LCP (liquid crystal polymer), polyimide or ABS resin. Composed.

  The resin fastening portions 60a, 60b, and 60c are formed in the notch portions provided in the metal plates constituting the first metal separator 22 to the third metal separator 28 by caulking, bonding, or the like, in advance, by molding a molded product formed with an insulating resin. It may be fixed. Alternatively, an insulating resin may be integrally injection-molded in the cutout portion of the metal plate.

  As shown in FIGS. 3 and 4, the resin fastening portion 60 a provided in the first metal separator 22 integrally forms a connecting pin portion (resin protruding portion) 62 protruding toward the surface 22 a side. As shown in FIG. 3, the resin fastening portions 60b and 60c provided in the second metal separator 26 and the third metal separator 28 have a first hole portion (first assembly hole) into which the connecting pin portion 62 is integrally inserted. Part) 64 is formed penetrating in the stacking direction.

  In the resin fastening portions 60a, 60b and 60c, a rebuilt pin (resin connecting member) 70, which will be described later, can be selectively disposed. At least a second hole (second assembly hole) 66a and a third hole (first 3 assembling holes) 66b are formed. The resin fastening portions 60a, 60b and 60c are formed with a fourth hole portion (end portion assembly hole portion) 68 into which a resin pin member (end portion resin connecting member) 92 described later is inserted. The second hole portion 66a, the third hole portion 66b, and the fourth hole portion 68 are coaxially disposed at the resin fastening portions 60a, 60b, and 60c in the stacking direction. In addition, the arrangement position on the plane in the resin fastening parts 60a, 60b, and 60c of the 1st hole part 64, the 2nd hole part 66a, the 3rd hole part 66b, and the 4th hole part 68 is limited to this embodiment. It is not a thing and can be set arbitrarily.

  As shown in FIGS. 3 and 5, the rebuilt pin 70 used in place of the connecting pin portion 62 is made of an insulating resin, similarly to the resin fastening portions 60 a to 60 c. The rebuilt pin 70 has a larger diameter than the second hole portion 66a and the third hole portion 66b of the first metal separator 22, and has a large diameter flange portion 70a that contacts the surface 22b side of the first metal separator 22. Have.

  The columnar portion 70b bulging from the flange portion 70a is selectively inserted into each second hole portion 66a or the third hole portion 66b. The distal end of the columnar portion 70b constitutes a head portion 70c whose diameter has been increased by a welding process described later, and this head portion 70c is locked to the surface 28b side of the third metal separator 28.

  The rebuilt pin 70 may be configured so as to be expandable and contractable in the radial direction by forming a head portion 70c in advance and providing a plurality of slits in the axial direction in the head portion 70c.

  As shown in FIG. 1, terminal portions 72a and 72b extending outward in the stacking direction are provided at substantially the center of the terminal plates 16a and 16b. The terminal portions 72a and 72b are inserted into the insulating cylinder 74 and inserted into the holes 76a and 76b of the insulating members 18a and 18b. The terminal portions 72a and 72b protrude through the holes 78a and 78b of the end plates 20a and 20b to the outside of the end plates 20a and 20b.

  The insulating members 18a and 18b are made of an insulating material such as polycarbonate (PC) or phenol resin. The insulating member 18a is provided with a rectangular recess 80a at the center, and the hole 76a communicates with the approximate center of the recess 80a. The terminal plate 16a is accommodated in the recess 80a, and the terminal portion 72a of the terminal plate 16a is inserted into the hole 76a with the insulating cylinder 74 interposed therebetween.

  The insulating member 18b is configured to be thicker than the insulating member 18a, and has a recess 80b in which an end on the laminated body 14 side is opened. A hole 76b communicates with the approximate center of the bottom surface forming the recess 80b. A stepped hole 82 is formed coaxially with the fourth hole 68 of the laminated body 14 at the outer peripheral edge of the insulating member 18b (see FIG. 2).

  The recess 80b of the insulating member 18b accommodates the conductive heat insulating member 84 and the terminal plate 16b, and the terminal portion 72b of the terminal plate 16b is inserted into the hole 76b with the insulating cylinder 74 interposed therebetween. The heat insulating member 84 includes, for example, at least a first heat insulating member 86 and a second heat insulating member 88 that are different from each other, and the first heat insulating member 86 and the second heat insulating member 88 are alternately stacked. The first heat insulating member 86 is made of, for example, a corrugated metal plate, while the second heat insulating member 88 is made of, for example, a carbon plate.

  The heat insulating member 84 may be configured by, for example, laminating two types (or three sets) of two corrugated metal plates alternately. The heat insulating member 84 only needs to be a member that retains pores and has electrical conductivity, and is made of an electrically conductive foam metal, honeycomb-shaped metal (honeycomb member), or porous carbon (for example, carbon paper). You may comprise either. The heat insulating member 84 may be a single sheet or a plurality of sheets.

  As shown in FIGS. 1 and 2, a holding member, for example, a resin pin member 92 is inserted into each stepped hole 82 of the insulating member 18b from the large diameter side. The resin pin member 92 has a head portion 92 a that abuts against a step wall surface of the stepped hole portion 82, and penetrates the small diameter side of the stepped hole portion 82 from the fourth hole portion 68 of the second metal separator 26. It is inserted into the fourth hole 68 of the three metal separator 28 integrally.

  The front end portion (the end opposite to the head portion 92a) of the resin pin member 92 protrudes outward from the fourth hole 68, and the front end portion is subjected to a heat caulking process so that a large amount is obtained. A caulking portion 92b having a diameter is provided. A resin holding portion 94 is configured through the resin pin member 92 and the fourth hole portion 68.

  Note that a resin pin member 92 may be used on the insulating member 18a side, similarly to the insulating member 18b side. At that time, if a stepped hole is formed in the insulating member 18a, and the resin pin member 92 is integrally inserted into the second metal separator 26 adjacent to the insulating member 18a and the fourth hole 68 of the first metal separator 22. Good.

  The operation of the fuel cell stack 10 configured as described above will be described below.

  First, as shown in FIG. 1, an oxidant gas such as an oxygen-containing gas is supplied to the oxidant gas inlet communication hole 36a of the end plate 20a. A fuel gas such as a hydrogen-containing gas is supplied to the fuel gas inlet communication hole 38a of the end plate 20a, while a cooling medium such as pure water, ethylene glycol, or oil is supplied to the pair of cooling medium inlet communication holes of the end plate 20a. 40a.

  As shown in FIG. 3, the oxidant gas flows from the oxidant gas inlet communication hole 36 a to the first oxidant gas channel 46 of the second metal separator 26 and the second oxidant gas channel 50 of the third metal separator 28. be introduced. The oxidant gas moves in the direction of arrow C and is supplied to the cathode electrodes 34 of the first electrolyte membrane / electrode structure 24a and the second electrolyte membrane / electrode structure 24b.

  On the other hand, the fuel gas is introduced into the first fuel gas channel 42 of the first metal separator 22 and the second fuel gas channel 48 of the second metal separator 26 from the fuel gas inlet communication hole 38a. The fuel gas moves in the direction of arrow C along the first fuel gas flow path 42 and the second fuel gas flow path 48, and each of the first electrolyte membrane / electrode structure 24a and the second electrolyte membrane / electrode structure 24b. It is supplied to the anode electrode 32.

  Therefore, in the first electrolyte membrane / electrode structure 24a and the second electrolyte membrane / electrode structure 24b, the oxidant gas supplied to each cathode electrode 34 and the fuel gas supplied to each anode electrode 32 are electrodes. Electricity is generated by being consumed by an electrochemical reaction in the catalyst layer.

  Next, the oxidant gas consumed by being supplied to the cathode electrode 34 is discharged in the direction of arrow A along the oxidant gas outlet communication hole 36b. Similarly, the fuel gas consumed by being supplied to the anode electrode 32 is discharged in the direction of arrow A along the fuel gas outlet communication hole 38b.

  In addition, the cooling medium supplied to the cooling medium inlet communication hole 40a is introduced into the cooling medium flow path 44 between the first metal separator 22 and the third metal separator 28 adjacent to each other, and then first, in the direction of arrow B Circulate in The cooling medium flows in the direction of arrow C to cool the first electrolyte membrane / electrode structure 24a and the second electrolyte membrane / electrode structure 24b, and then flows in the direction of arrow B through each cooling medium outlet communication hole 40b. Discharged.

  In this case, in the first embodiment, as shown in FIG. 5, the connecting pin portion 62 is integrally formed with the resin fastening portion 60 a provided in the first metal separator 22. The connecting pin portion 62 is inserted into the first hole 64 of each of the second metal separator 26 and the third metal separator 28 and then welded to the tip of the head portion 62a of the connecting pin portion 62 to generate power. The cell 12 is assembled.

  Next, when the assembled fuel cell stack 10 is disassembled for parts replacement or analysis due to a failure or the like, first, the head 62a of the connecting pin portion 62 is removed, and the power generation cells 12 are connected to each other. To be separated. On the other hand, a rebuilt pin 70 configured individually is prepared.

  Further, the first metal separator 22, the first electrolyte membrane / electrode structure 24a, the second metal separator 26, the second electrolyte membrane / electrode structure 24b, and the third metal separator 28 are laminated. In this state, the rebuilt pin 70 is integrally inserted into each third hole 66b, for example.

  As shown in FIG. 5, in the rebuilt pin 70, the column body portion 70 b is integrally inserted into each third hole portion 66 b, and the flange portion 70 a is abutted and supported by the first metal separator 22. In this state, for example, a welding process is performed on the front end of the columnar body part 70b via a welding tip to form a head part 70c. Therefore, the power generation cell 12 is integrally sandwiched between the flange portion 70a and the head portion 70c of the rebuilt pin 70, and reassembly is performed.

  Here, in the power generation cells 12 adjacent to each other, the rebuilt pin 70 is inserted into the third hole 66b constituting one power generation cell 12, and the rebuilt pin is inserted into the second hole 66a constituting the other power generation cell 12. 70 is inserted. For this reason, in the power generation cells 12 adjacent to each other, the rebuilt pins 70 are arranged in a staggered manner along the stacking direction.

  Further, in the first embodiment, as shown in FIG. 2, a recess 80b is formed in the insulating member 18b, and a heat insulating member 84 and a terminal plate 16b are accommodated in the recess 80b. Then, in a state where the second metal separator 26 is laminated on the insulating member 18b, each resin pin member 92 is inserted into each fourth hole of the second metal separator 26 and the third metal separator 28 from each stepped hole portion 82 of the insulating member 18b. The hole 68 is integrally inserted.

  Next, a heat caulking process is performed on the tip of the resin pin member 92 to provide a caulking portion 92b. The resin pin member 92 and the insulating member 18b may be integrated, and screwing, clips, bands, or the like may be employed in addition to heat caulking.

  As described above, in the first embodiment, the power generation cell 12 is integrated through the resin fastening portions 60a, 60b, and 60c, and the reassembly operation of the power generation cell 12 can be quickly performed. In addition, the second metal separator 26 and the third metal separator 28 that are end power generation cells adjacent to the insulating member 18 b are integrally held by the insulating member 18 b via the resin holding portion 94.

  For this reason, it becomes possible to simplify the handling of parts and to improve the assembly workability satisfactorily. Furthermore, the 4th hole 68 which comprises the resin holding | maintenance part 94 is provided in the 1st metal separator 22, the 2nd metal separator 26, and the 3rd metal separator 28 which are all the separators. Accordingly, the separator structure can be shared, and the cost can be favorably suppressed.

  FIG. 6 shows a fuel cell stack 100 according to the second embodiment of the present invention. The same components as those of the fuel cell stack 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The fuel cell stack 100 includes a stacked body 104 in which a plurality of power generation cells 102 are stacked in the horizontal direction (arrow A direction). A terminal plate 106a, an insulating member 108a, and an end plate 110a are sequentially arranged at one end in the stacking direction (arrow A direction) of the stacked body 104 toward the outside. At the other end in the stacking direction of the stacked body 104, a terminal plate 106b, an insulating member 108b, and an end plate 110b are sequentially disposed outward.

  As shown in FIGS. 7 and 8, the power generation cell 12 includes an electrolyte membrane / electrode structure 112, and a first metal separator 114 and a second metal separator 116 that sandwich the electrolyte membrane / electrode structure 112. The electrolyte membrane / electrode structure 112 includes a solid polymer electrolyte membrane 30a, and an anode electrode 32a and a cathode electrode 34a that sandwich the solid polymer electrolyte membrane 30a. The solid polymer electrolyte membrane 30a has a larger planar dimension than the anode electrode 32a and the cathode electrode 34a.

  An oxidant gas inlet communication hole 36a, a coolant inlet communication hole 40a, and a fuel gas outlet communication hole 38b communicate with each other in the arrow A direction at one end edge of the power generation cell 102 in the arrow B direction. Are arranged in the vertical direction). A fuel gas inlet communication hole 38a, a coolant outlet communication hole 40b, and an oxidant gas outlet communication hole 36b communicate with each other in the arrow A direction at the other edge of the power generation cell 102 in the arrow B direction. Are provided in an array.

  On the surface 114a of the first metal separator 114 facing the electrolyte membrane / electrode structure 112, for example, a fuel gas channel 42a extending in the arrow B direction is formed. On the surface 116a of the second metal separator 116 facing the electrolyte membrane / electrode structure 112, for example, an oxidant gas channel 46a extending in the direction of arrow B is provided.

  A cooling medium flow path 44 is formed between the surface 114 b of the first metal separator 114 and the surface 116 b of the second metal separator 116 that are adjacent to each other. The cooling medium flow path 44 is formed by overlapping the back surface shape of the fuel gas flow path 42a and the back surface shape of the oxidant gas flow path 46a.

  As shown in FIG. 8, a plurality of resin fastening portions 118 a and 118 b are provided on the outer peripheral edge portions of the first metal separator 114 and the second metal separator 116 (in this embodiment, four locations at four corners). The resin fastening portion 118a is provided with a fourth hole 68, a first hole 64, a second hole 66a, and a third hole 66b arranged vertically. The resin fastening portion 118b is provided with a fourth hole portion 68, a connecting pin portion 62, a second hole portion 66a, and a third hole portion 66b arranged vertically. The second hole portion 66a, the third hole portion 66b, and the fourth hole portion 68 are coaxially disposed at the resin fastening portions 118a and 118b in the stacking direction.

  As shown in FIG. 7, the conductive heat insulating member 120 and the terminal plate 106b are accommodated in the recess 80b of the insulating member 108b. The heat insulating member 120 is configured by alternately laminating, for example, two sets of corrugated metal plates 122 having electrical conductivity and corrugated metal plates 124 having electrical conductivity.

The heat insulating member 120 and the terminal plate 106b are accommodated in the recess 80b of the insulating member 108b, and the end power generation cell 102 _end is stacked on the insulating member 108b. In this state, each resin pin member 92 is integrally inserted into each stepped hole 82 of the insulating member 108b and each fourth hole 68 of the _end power generation cell 102 _end . And the crimping part 92b is provided in the front-end | tip part of the resin pin member 92, and the edge power generation cell _102end is integrated with the insulating member 108b.

In the second embodiment configured as described above, the power generation cell 102 is integrated via the resin fastening portions 118a and 118b, and the reassembly operation of the power generation cell 102 can be quickly performed. In addition, the end power generation cell 102 _end adjacent to the insulating member 108 b is integrally held by the insulating member 108 b via the resin holding portion 94.

  For this reason, it is possible to simplify the handling of the components, improve the assembly workability satisfactorily, and reduce the cost, and the same effects as those of the first embodiment described above can be obtained. can get.

DESCRIPTION OF SYMBOLS 10, 100 ... Fuel cell stack 12, 12 _end , 102 ... Power generation cell 14, 104 ... Laminated body 16a, 16b, 106a, 106b ... Terminal plate 18a, 18b, 108a, 108b ... Insulating member 20a, 20b, 110a, 110b ... End plates 22, 26, 28, 114, 116 ... metal separators 24a, 24b, 112 ... electrolyte membrane / electrode structures 30, 30a ... solid polymer electrolyte membranes 32, 32a ... anode electrodes 34, 34a ... cathode electrodes 42, 48 ... fuel gas passage 44 ... cooling medium passage 46, 50 ... oxidant gas passages 52, 54, 56 ... first seal members 60a, 60b, 60c, 118a, 118b ... resin fastening portion 62 ... coupling pin portion 64, 66a, 66b, 68 ... hole 70 ... rebuilt pin 84, 120 ... heat insulation member 92 ... resin pin Wood 94 ... resin holding portion

Claims (1)

A power generation cell that sandwiches an electrolyte / electrode structure having electrodes disposed on both sides of the electrolyte between separators, and a terminal plate and an insulating member are disposed on both sides in the stacking direction of the stacked body in which the plurality of power generation cells are stacked. And a fuel cell stack in which the end plate is disposed outwardly,
On the outer peripheral edge of the separator, a resin fastening portion that fastens between the separators arranged in the stacking direction in the power generation cell;
A resin holding part for holding the separator constituting the end power generation cell disposed at least at one end in the stacking direction on one of the insulating members;
Is configured,
The resin fastening portion includes a resin protrusion provided integrally with the separator disposed at one end of the power generation cell;
A first assembly hole formed in the separator other than the separator provided with the resin projection, and the resin projection is inserted integrally;
A second assembly hole portion and a third assembly hole portion, which are formed in all the separators, and in which a resin connecting member as a separate member is selectively inserted instead of the resin projection portion;
While having
The resin holding portion is formed in all of the separators, and an end assembly hole in which an end resin connecting member, which is a separate member, is integrally inserted from the insulating member into the separator of the end power generation cell. A fuel cell stack comprising:

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